Dye compounds, compositions containing them and their use

ABSTRACT

Azo dyes of Formula (1) have utility as dyes for ink-jet printing where Formula (1) represents:                    
     which comprises any suitable form of the compound: such as salt; stereoisomer, zwitterion, polymorph, complex, isotopic form, combinations thereof in the same species and mixtures thereof; where: 
     p represents from 1 to 7 inclusive; 
     the napthyl moiety may be optionally substituted; 
     R 1  comprises at least one of the following substituents, optionally substituted: 
     H, C 1-4 -alkyl, NHCOC 1-4  alkyl, C 1-4  alkoxy, NHCOaryl, NHSO 2 C 1-4  alkyl, NHSO 2 aryl, 
     NHCONR 3 R 4  where R 3  and R 4  each independently comprises H, C 1-4 alkyl or aryl; 
     R 2  comprises H, C 1-4  alkyl or C 1-4  alkoxy; 
     L 1  and L 2  each independently comprises at least one of the following substituents, optionally substituted: 
     —NH 2 , —NHC 1-4  alkyleneOH, —SC 1-4 alkylene —SO 3 H, —NHC 1-4 alkyleneN(C 1-4 alkyl) 2 , —N(C 1-4 alkyleneOH) 2 , —NHC 1-4 alkyleneSO 3 H, —NHC 1-4 alkylene(CO 2 H) n  where n is 1, 2 or 3, —SC 1-4 alkylene(CO 2 H) m  where m is 1, 2 or 3, 
     a moiety of Formula (2):                    
     where: 
     X represents NHC 1-4 alkylene or a direct link and Y represents O or NH; 
     amoiety of Formula (3):                    
     where: 
     q represents from 1 to 7 inclusive; 
     the napthyl moiety may be optionally substituted; and 
     R 5  and R 6  each independently comprises at least one of the following substituents, optionally substituted: H, C 1-4 -alkyl, NHCOC 1-4  alkyl, C 1-4  alkoxy, NHCOaryl, NHSO 2 C 1-4  alkyl, NHSO 2 aryl and NHCONR 7 R 8  where R 7  and R 8  each independently comprises H, C 1-4 alkyl, aryl; and 
     any other suitable labile or non-labile substituent not mentioned above; 
     where the optional substituents herein comprise: C 1-4 alkyl (optionally substituted with at least one halo), C 1-4 alkoxy (optionally substituted with at least one halo), carboxy, sulpho, hydroxy, amino, mercapto, cyano, nitro and halo.

COMPOUNDS COMPOSITION AND USE

This invention relates to dyes, to inks and to their use in ink jetprinting (“IJP”). IJP is a non-impact printing technique in whichdroplets of ink are ejected through a fine nozzle onto a substratewithout bringing the nozzle into contact with the substrate.

There are many demanding performance requirements for dyes and inks usedin IJP. For example they desirably provide sharp, non-feathered imageshaving good water-fastness, light-fastness and optical density. The inksare often required to dry quickly when applied to a substrate to preventsmudging, but they should not form a crust over the tip of an ink jetnozzle because this will stop the printer from working. The inks shouldalso be stable to storage over time without decomposing or forming aprecipitate which could block the fine nozzle.

According to the present invention there is provided at least onecompound of Formula (1):

which comprises any suitable form of the compound: such as salt;stereoisomer, zwitterion, polymorph, complex, isotopic form,combinations thereof in the same species and mixtures thereof; where:

p represents from 1 to 7 inclusive;

the napthyl moiety may be optionally substituted;

R¹ comprises at least one of the following substituents, optionallysubstituted:

H, C₁₋₄-alkyl, NHCOC₁₋₄ alkyl, C₁₋₄ alkoxy, NHCOaryl, NHSO₂C₁₋₄ alkyl,NHSO₂aryl, NHCONR³R⁴ where R³ and R⁴ each independently comprises H,C₁₋₄alkyl or aryl;

R² comprises H, C₁₋₄ alkyl or C₁₋₄ alkoxy;

L¹ and L² each independently comprises at least one of the followingsubstituents, optionally substituted:

—NH₂, —NHC₁₋₄ alkyleneOH, —SC₁₋₄alkylene —SO₃H,—NHC₁₋₄alkyleneN(C₁₋₄alkyl)₂, —N(C₁₋₄alkyleneOH)₂, —NHC₁₋₄alkyleneSO₃H,—NHC₁₋₄alkylene(CO₂H)_(n) where n is 1, 2 or 3, —SC₁₋₄alkylene(CO₂H)_(m)where m is 1, 2 or 3,

a moiety of Formula (2):

where:

X represents NHC₁₋₄alkylene or a direct link and Y represents O or NH;

a moiety of Formula (3):

where:

q represents from 1 to 7 inclusive;

the napthyl moiety may be optionally substituted; and

R⁵ and R⁶ each independently comprises at least one of the followingsubstituents, optionally substituted: H, C₁₋₄-alkyl, NHCOC₁₋₄ alkyl,C₁₋₄ alkoxy, NHCOaryl, NHSO₂C₁₋₄ alkyl, NHSO₂aryl and NHCONR⁷R⁸ where R⁷and R⁸ each independently comprises H, C₁₋₄alkyl, aryl; and

any other suitable labile or non-labile substituent not mentioned above;

where the optional substituents herein comprise: C₁₋₄alkyl (optionallysubstituted with at least one halo), C₁₋₄alkoxy (optionally substitutedwith at least one halo), carboxy, sulpho, hydroxy, amino, mercapto,cyano, nitro and halo;

with the provisos that when p is 2 and the two —SO₃H groups in thenaphthyl moiety are in the 3 and 7 positions, and, if L¹ or L² areFormula (3), q is 2 and the two —SO₃H groups in the naphthyl moiety arein the 3 and 7 positions then:

(a) L¹ and L² cannot both be a group of Formula (3);

(b) when R² is H, R¹ is CH₃ in the ortho position with respect to theazo group in Formula (1) and L¹ is a group of Formula (3) in which R⁶ isH and R⁵ is CH₃ in the ortho position with respect to the azo group inFormula (3) then: L² is other than NH₂ or NHC₂H₄OH; and

(c) when R² is H, R¹ is OCH₃ in the ortho position with respect to theazo group in Formula (1) and L¹ is a group of Formula (3) in which R⁶ isH and R⁵ is OCH₃ in the ortho position with respect to the azo group inFormula (3) then: L² is other than NHC₂H₄OH.

When L¹ and/or L² represent a labile atom or group, it is preferably anatom or group which is bound by a chemical bond to the triazine nucleuswhich is displaceable by a hydroxyl group of cellulose under mildlyalkaline aqueous conditions to form a covalent bond between the triazinenucleus and cellulose. Labile atoms and groups that may be representedby L¹ and/or L² independently corprise: halo (preferably F and Cl);sulphonic acid groups; thiocyano groups; optionally substitutedquatemary ammonium groups (preferably trialkylammonium groups) and/oroptionally substituted pyridinium groups (preferably 3- and 4-carboxypyridinium groups).

Preferred non-labile groups represented by L¹ and/or L² independentlycomprise groups of the formulae —OR⁹, —SR¹⁰ and/or —NR¹¹R¹², morepreferably —OH,—NH₂, —NH(C₁₋₄alkyl) and/or —NH(hydroxyC₂₋₄alkyl). In thepreceding formulae R⁹, R¹⁰, R¹¹ and/or R¹² are each independentlyselected from the following optionally substituted substituents: H;alkyl (preferably C₁₋₁₀alkyl, especially C₁₋₄alkyl); cycloalkyl; aryl(preferably phenyl); aralkyl [preferably —(CH₂)₁phenyl, especiallybenzyl]; and R¹¹ and R¹² together with the nitrogen atom to which theyare attached form an optionally substituted 5- or 6-membered ring,preferably an optionally substituted morpholine, piperidine orpiperazine ring, more preferably piperazine in which the free ringN-atom is optionally substituted by a C₁₋₄-alkyl or hydroxy-C₂₋₄alkylgroup. When R⁹, R¹⁰, R¹¹ and/or R¹² is substituted, the substituent ispreferably selected from the optional substituents listed above, morepreferably is selected from: hydroxy, methyl, methoxy, sulpho andcarboxy.

Any radical group mentioned above as a substituent refers to amonovalent radical unless otherwise stated. A group which comprises achain of three or more atoms signifies a group in which the chain whollyor in part may be linear, branched and/or form a ring (including spiroand/or fused rings). The total number of certain atoms is specified forcertain substituents for example C_(1-n)alkyl, signifies an alkyl groupcomprising from 1 to n carbon atoms. In any of the formulae drawn hereinif one or more ring substituents are not indicated as attached to anyparticular atom on the ring, for example the —CO₂H groups in Formula(1), the substituent may replace any H attached to an atom in the ringand may be located at any available position on the ring. Hydrocarbonsubstituents or parts of substituents may comprise one or more doubleand/or triple carbon to carbon bonds and the term ‘alkyl’ as used hereinencompasses alkenyl and alkynyl. The term ‘aryl’ as used hereincomprises any suitable hydrocarbon comprising an aromatic moiety. Theterm ‘halo’ as used herein signifies fluoro, chloro, bromo and iodo.

The terms ‘acceptable’ or ‘suitable’ (for example with reference tocomposition ingredients, substituents and/or compounds described herein)will be understood to mean suitable for use in IJP for example byproviding desirable properties to the ink or being compatible with anyinert carriers and/or diluents suitable for formulating such inks. Inrelation to the processes described herein suitable compounds are thosewhich will, in addition, undergo the specified reactions. To beparticularly acceptable for use in IJP compounds of Formula (1) may beAmes negative.

Preferred dyes of Formula (1) are those in which p is 2, more preferablythe two —SO₃H groups are attached to the napthyl moiety in Formula (1)at the 3 and 7 positions.

When L¹ or L² comprise a moiety of Formula (2), preferably Y is O.

When L¹ or L² comprise a moiety of Formula (3), preferably q is 2, morepreferably the two —SO₃H groups are attached to the napthyl moiety inFormula (3) at the 3 and 7 positions.

When R¹ and R⁶ are alkyl they are preferably CH₃.

More preferred dyes of Formula (1) are those in which R¹ and R⁶ are bothNHCOCH₃; R³, R⁴, R⁷ and R⁸ are all H; and n and m is each independently1 or 2.

Specific compounds of Formula (1) comprise those compounds exemplifiedherein; any suitable salts thereof, preferably the sodium salts; and anysuitable mixtures thereof.

Compounds of Formula (1) may be in the form as shown in the structuresherein (e.g. free acid form) but are preferably in the form of salts.Salts of Formula (1) may be formed from one or more organic and/orinorganic base(s) or acid(s) and compounds of Formula (1) which areacidic and/or basic (for example acid and/or base addition salts). Saltsof Formula (1) comprise all acceptable salts that may be formed frommonovalent and/or multivalent acids and/or bases. Salts of Formula (1)also comprise all enantiomeric salts formed with acceptable chiral acidsand/or bases and/or any mixtures of enantiomers of such salts (forexample racemic mixtures). Preferred salts are alkali metal salts,especially lithium, sodium and potassium salts, ammonium and substitutedammonium salts. Especially preferred salts are sodium salts. The dyesmay be converted into a salt using known techniques. The presentinvention comprises all acceptable salts of Formula (1) and any suitablemixtures thereof.

Certain compounds of Formula (1) may exist as one or more stereoisomers,for example, enantiomers, diastereoisomers, geometric isomers,tautomers, conformers and/or suitable combinations thereof possible inthe same species. It is particularly preferred that dyes of Formula (1)comprise all tautomeric forms including those not Aspecificallyillustrated herein. The present invention comprises all acceptablestereoisomers of compounds of Formula (1) and any suitable mixturesthereof.

Certain compounds of Formula (1) may exist as one or more zwitterions,for example, species which comprise two or more centres of ionic charge.The present invention comprises all acceptable zwitterions of Formula(1) and any suitable mixtures thereof.

Certain compounds of Formula (1) may exist as one or more polymorphs,for example, phases, crystalline forms, amorphous forms, solidsolutions, interstitial compounds and/or any suitable mixtures thereof.The present invention includes all acceptable polymorphs of Formula (1)and any suitable mixtures thereof.

Certain compounds of Formula (1) may exist in the form of one or morecomplexes, for example, chelates, solvates, organometallic complexes,and/or complexes with other suitable ligands. Such complexes may beformed between an acceptable substrate in which the compound of Formula(1) and/or the substrate may act as a ligand. The substrate may compriseone or more acceptable solvents to form solvates. The complexes may benon-stoichiometric, for example if the complex is a hydrate it maycomprise a hemihydrate, monohydrate and/or dihydrate. The presentinvention includes all acceptable complexes of Formula (1) and anysuitable mixtures thereof.

Certain compounds of Formula (1) may exist as one or more isotopic formsin which one or more atoms in Formula (1) comprise one or more suitableisotopes. The natural ratios of various isotopes may be altered bysuitable means, for example certain ¹²C atoms in certain compounds ofFormula (1) may be substantially replaced by the less common ¹⁴C and/or¹³C isotopes. Optionally certain isotopic forms of Formula (1) may beradio-active. Certain of the isotopic forms of Formula (1) may be usedas means for selective imaging in imaging devices (for example devicesusing X-rays, positron emission tomography and/or nuclear magneticresonance); and/or as tools to investigate the mode of action ofcompounds of Formula (1) in IJP. The present invention includes allacceptable, isotopic forms of Formula (1) and any suitable mixturesthereof.

The present invention relates to all compounds of Formula (1) even thosewhich may not be directly acceptable for use in IJP because they exhibitundesirable properties. Such compounds may nevertheless have utility inthe field of the present invention for example as intermediates in thepreparation and/or purification of acceptable compounds of Formula (1)and/or as research tools and/or diagnostic aids in relation to IJP.

Compounds of Formula (1) may be prepared by any suitable methodsanalogous to those described in the art for similar azo compounds.

Compounds of Formula (1) may also be prepared by a method describedbelow in steps i) to iii):

i) diazotising an aromatic amine of Formula (4):

to form the corresponding diazonium salt and coupling with a compound ofFormula (5):

ii) condensing the resulting azo compound preferably in the presence ofa base with cyanuric chloride to form a compound of Formula (6):

iii) condensing the compound of Formula (6) with compounds of formulaeL¹H and L²H in which p, R¹, R², L¹ and L² are as defined herein, to forma compound of Formula (1).

The reactions leading to the formation of the compounds of Formula (1)may be performed under conditions that have been described in the art.For example diazotisation is preferably performed at a temperature below6° C., more preferably at a temperature in the range −10° C. to 5° C.Preferably the diazotisation is performed in water, more preferably at apH below 7. Dilute mineral acids, such as HCl or H₂SO₄, are often usedto achieve the desired acidic conditions. The azo dyes may be isolatedby known methods such as spray drying or precipitation followed byfiltration.

An aspect of the present invention comprises an ink comprising at leastone compound of Formula (1) as defined herein, without the provisosgiven above, and a suitable medium.

According to a further aspect of the present invention there is providedan ink comprising:

(a) from 0.01 to 30 parts of a dye of the Formula (1); and

(b) from 70 to 99.99 parts of a liquid medium or a low melting pointsolid medium; wherein all parts are by weight and the number of parts of(a)+(b)=100.

The number of parts of component (a) is preferably from 0.1 to 20, morepreferably from 0.5 to 15, and especially from 1 to 5 parts. The numberof parts of component (b) is preferably from 99.9 to 80, more preferablyfrom 99.5 to 85, especially from 99 to 95 parts.

When the medium is a liquid, preferably component (a) is completelydissolved in component (b). Preferably component (a) has a solubility incomponent (b) at 20° C. of at least 10%. This allows the preparation ofconcentrates which may be used to prepare more dilute inks and reducesthe chance of the dye precipitating if evaporation of the liquid mediumoccurs during storage.

Preferred liquid media include water, a mixture of water and an organicsolvent and an organic solvent free from water.

When the medium comprises a mixture of water and an organic solvent, theweight ratio of water to organic solvent is preferably from 99:1 to1:99, more preferably from 99:1 to 50:50 and especially from 95:5 to80:20. Preferably the organic solvent comprising the mixture of waterand organic solvent is a water-miscible organic solvent or a mixture ofsuch solvents. The liquid medium may comprise water and preferably twoor more, more preferably from 2 to 8, water-soluble organic solvents.

Preferred water-miscible organic solvents comprise:

C₁₋₆-alkanols, preferably methanol, ethanol, n-propanol, isopropanol,n-butanol, sec-butanol, tert-butanol, n-pentanol, cyclopentanol and/orcyclohexanol;

linear amides, preferably dimethylformamide and/or dimethylacetamide;

ketones and/or ketone-alcohols, preferably acetone, methyl ether ketone,cyclohexanone and/or diacetone alcohol;

water-miscible ethers, preferably tetrahydrofuran and/or dioxane;

diols, preferably C₂₋₁₂diols (for example pentane-1,5-diol, ethyleneglycol, propylene glycol, butylene glycol, pentylene glycol, hexyleneglycol and/or thiodiglycol) and/or oligo- and/or poly-alkyleneglycols(for example diethylene glycol, triethylene glycol, polyethylene glycoland/or polypropylene glycol);

triols, preferably glycerol and/or 1,2,6-hexanetriol;

C₁₋₄alkyl ethers of diols, preferably monoC₁₋₄alkyl ethers ofC₂₋₁₂diols: {for example 2-methoxyethanol, 2-(2-methoxyethoxy)ethanol,2-(2-ethoxyethoxy)-ethanol, 2-[2-(2-methoxyethoxy)ethoxy] -ethanol,2-[2-(2-ethoxyethoxy)-ethoxy]-ethanol and/or ethyleneglycol monoallylether};

cyclic amides, preferably 2-pyrrolidone, N-methyl-2-pyrrolidone,N-ethyl-2-pyrrolidone,

caprolactam and/or 1,3-dimethylimidazolidone;

cyclic esters, preferably caprolactone;

sulphoxides, preferably dimethyl sulphoxide and/or sulpholane; and/orany suitable mixtures thereof.

More preferred water-soluble organic solvents are selected from:

cyclic amides (e.g. 2-pyrrolidone, N-methyl-pyrrolidone andN-ethyl-pyrrolidone); diols, (e.g. 1,5-pentane diol, ethyleneglycol,thiodiglycol, diethyleneglycol and triethyleneglycol);

C₁₋₄alkyl ethers of diols (e.g. 2-methoxy-2-ethoxy-2-ethoxyethanol); andany suitable mixtures thereof.

A preferred liquid medium comprises:

(a) from 75 to 95 parts water; and

30 (b) from 25 to 5 parts in total of one or more solvents selectedfrom:

diethylene glycol, 2-pyrrolidone, thiodiglycol, N-methylpyrrolidone,cyclohexanol, caprolactone, caprolactam and pentane-1,5-diol;

where the parts are by weight and the sum of the parts (a)+(b)=100.

Another preferred liquid medium comprises:

(a) from 60 to 80 parts water;

(b) from 2 to 20 parts diethylene glycol; and

(c) from 0.5 to 20 parts in total of one or more solvents selected from:

2-pyrrolidone, N-methylpyrrolidone, cyclohexanol, caprolactone,caprolactam, pentane-1,5-diol and thiodiglycol;

where the parts are by weight and the sum of the parts (a)+(b)+(c)=100.

Examples of further suitable media for inks of the present inventioncomprise a mixture of water and one or more organic solvents aredescribed in U.S. Pat. No. 4,963,189, U.S. Pat. No. 4,703,113, U.S. Pat.No. 4,626,284 and EP 0425150-A.

When the liquid medium comprises an organic solvent free from water,(i.e. less than 1% water by weight) the solvent preferably has a boilingpoint of from 300 to 200° C., more preferably of from 400 to 150° C.,especially from 50 to 125° C. The organic solvent may bewater-immiscible, water-miscible or a mixture of such solvents.Preferred water-miscible organic solvents comprise any of thosedescribed above and mixtures thereof. Preferred water-immisciblesolvents comprise aliphatic hydrocarbons; esters (for example ethylacetate) chlorinated hydrocarbons (for example dichloromethane), ethers(for example diethyl ether) and mixtures thereof.

When the liquid medium comprises a water-immiscible organic solvent,preferably it comprises a polar solvent (for example a C₁alkanol) toenhance the solubility of the dye in the liquid medium. It is especiallypreferred that where the liquid medium is an organic solvent free fromwater it comprises a ketone (especially methyl ethyl ketone) andlor analcohol (especially a C₁₋₄alkanol, more especially ethanol or propanol).

The organic solvent free from water may be a single organic solvent or amixture of two or more organic solvents. It is preferred that when themedium is an organic solvent free from water it is a mixture of 2 to 5different organic solvents. This allows a medium to be selected whichgives good control over the drying characteristics and storage stabilityof the ink.

Ink media comprising an organic solvent free from water are particularlyuseful where fast drying times are required and particularly whenprinting onto hydrophobic and non-absorbent substrates, for exampleplastics, metal and glass.

Preferred low melting solid media have a melting point in the range from60°C. to 125° C. Suitable low melting point solids include long chainfatty acids or alcohols, preferably those with C₁₈₋₂₄chains, andsulphonamides. The dye of Formula (1) may be dissolved in the lowmelting point solid or may be finely dispersed in it.

The ink may also contain additional components conventionally used ininks for IJP, for example viscosity and surface tension modifiers,corrosion inhibitors, biocides, kogation reducing additives andsurfactants which may be ionic or non-ionic.

A further aspect of the invention provides a process for printing animage on a substrate comprising applying an ink comprising a dye ofFormula (1) to the substrate by means of an ink jet printer. The inkused in this process is preferably an ink of the present invention asdefined herein.

The ink jet printer preferably applies the ink to the substrate in theform of droplets which are ejected through a small orifice onto thesubstrate. Preferred ink jet printers are piezoelectric ink jet printersand thermal ink jet printers. In thermal ink jet printers, programmedpulses of heat are applied to the ink in a reservoir by means of aresistor adjacent to the orifice, thereby causing the ink to be ejectedin the form of small droplets directed towards the substrate duringrelative movement between the substrate and the orifice. Inpiezoelectric ink jet printers the oscillation of a small crystal causesejection of the ink from the orifice.

The substrate is preferably paper, plastic, a textile, metal or glass,more preferably paper, an overhead projector slide or a textilematerial, especially paper. Preferred papers are plain or treated paperswhich may have an acid, alkaline or neutral character.

A further aspect of the present invention provides a paper, an overheadprojector slide or a textile material printed with an ink and/or a dyeas defined herein and/or by means of a process as defined herein.

When the substrate is a textile material the ink according to theinvention is preferably applied thereto by:

i) applying the ink to the textile material using an ink jet printer;and

ii) heating the printed textile material at a temperature of from 50° C.to 250° C.

Preferred textile materials are natural, synthetic and semi-syntheticmaterials. Examples of preferred natural textile materials include wool,silk, hair and cellulosic materials, particularly cotton, jute, hemp,flax and linen. Examples of preferred synthetic and semi-syntheticmaterials include polyamides, polyesters, polyacrylonitriles andpolyurethanes.

Preferably the textile material has been treated with an aqueouspretreatment composition comprising a thickening agent and optionally awater-soluble base and a hydrotropic agent and dried prior to step i)above.

The pre-treatment composition preferably comprises a solution of thebase and the hydrotropic agent in water containing the thickening agent.Particularly preferred pretreatment compositions are described morefully in EP 0534660-A.

The invention is further illustrated by the following Examples in whichall parts and percentages are by weight unless otherwise stated.

EXAMPLE 1 Preparation of

i) Preparation of

2-Aminonapthalene4,8-disulphonic acid (64.0 g) was stirred in water (400cm³) at pH 7, cooled to 0-10° C. and concentrated hydrochloric acid (100cm³) was added followed by sodium nitrite solution (100 cm³ of 2mol.dm⁻³) at 0-10° C. The reaction mixture was stirred for 1 hour beforethe excess nitrite was reacted with sulphamic acid.

A solution of m-aminoacetanilide in water (400 cm³) at pH 7 was added tothe diazo solution and buffer to pH 4 with sodium acetate. The reactionmixture was stirred for 16 hours and allowed to warm to 20° C. beforerecovering the solid by filtration. The filtered salt was washed withsaturated brine (500 cm³) and dried at 60° C. in an oven to give 101.2 gof product.

ii) The product (11.6 g) from i) above was stirred in water (300 cm³)and the pH adjusted to 8 with sodium hydroxide solution. Cyanuricchloride (4.6 g) in acetone (50 cm³) was added to the monoazo solutionat 0-10° C. maintaining the pH at 5-6 by addition of sodium hydroxidesolution (2 mol.dm⁻³). The reaction mixture was stirred for 2 hours.3-Mercapto-1-propanesulphonic acid (13.5 g) in water (100cm³) was addedand the reaction warmed to 55-60° C. and maintaining the pH at 8-9 withsodium hydroxide solution whilst stirring for 6 hours. The reactionmixture was cooled to 20° C. the pH adjusted to 7 with hydrochloric acidand acetone added to precipitate a solid. The solid was collected byfiltration washed with acetone and dried at 60° C. overnight to give thetitle compound (14.9 g).

EXAMPLE 2 Preparation of

i) Preparation of

the procedure of Example 1 i) was used except that aniline was used inplace of the m-aminoacetanilide to give 48 g of product.

ii) The product (12 g) from i) above was dissolved in water and cyanuricchloride (4 g) in acetone (25 cm³) was added dropwise at 0-5° C. Themixture was stirred at 0-5° C. for 30 minutes before adding a further 12g of product from i) above. The mixture was stirred at 20° C. and pH 6-7for 4 hours. Ethanolamine (3.7 g) was added and the pH adjusted to 9with sodium carbonate before stirring for 16 hours at 70° C. Sodiumchloride solution (10% w/v) was added and the solid precipitated wascollected by filtration and then dried at 75° C. overnight to give thetitle compound (14.2 g).

EXAMPLE 3 Preparation of

Prepared in an analogous fashion to Example 1 but using the monoazocompound from Example 2 together with excess HSC₃H₆SO₃H.

EXAMPLE 4 Preparation of

Prepared as Example 1 replacing HSC₃H₆SO₃H by morpholine.

EXAMPLE 5 Preparation of

Prepared as Example 1 replacing HSC₃H₆SO₃H byN,N-dimethylpropane-1,3-diamine.

EXAMPLE 6 Preparation of

Prepared by reaction of dichlorotriazine of Example 1 with excessHSC₃H₆SO₃H.

EXAMPLE 7 Preparation of

prepared by the method of Example 1 i) except that 3-methylaniline wasused in place of the m-aminoacetanilide.

ii) The title compound was prepared from the above monoazo compoundusing the method of Example 3.

EXAMPLE 8 Preparation of

Prepared as for Example 1 replacing HSC₃H₆SO₃H by ethanolamine.

EXAMPLE 9 Preparation of

Prepared as Example 1 replacing HSC₃H₆SO₃H by1-(2-aminoethyl)piperazine.

Salts

The exemplified compounds 1 to 8, prepared as described above, wereconverted to their purified sodium salts as follows. Each example wasstirred in water (400 cm³) to form a slurry the pH of which was adjustedto 9. The solution was dialysed until its conductivity was measured tobe less than 100 μScm⁻¹. The solution was then filtered through WhatmanGF/C and 0.45 μm filter papers (Example 2 used 1.6, 0.8, 0.45 and 0.2 μmfilter papers) to obtain a purified sodium salt suitable for usedirectly in an ink as described below.

Inks

The effectiveness in ink jet printing of compounds of Formula (1) wasdemonstrated as follows. Inks separately comprising each exemplified dyewere prepared by dissolving 2 parts of the sodium salt, prepared asdescribed above, in 98 parts of a mixture of water and 2-pyrrolidone (ina respective ratio of 90:10 by volume). The inks were printed onto plainpaper using a thermal ink-jet printer to give a bright yellow printwhich had good optical density and light fastness.]

Further inks comprising the exemplified dyes may be may be prepared asdescribed in the following tables in which the number in the firstcolumn (headed Ex. no.) denotes the example number of dye to be used inthe ink. The dye may be in its free acid form and/or in the form of anysuitable salt (e.g. sodium salt). Numbers quoted in the second columnonwards refer to the number of parts of the relevant ingredient and allparts are by weight. The inks may be applied to paper by thermal orpiezo ink jet printing.

The following abbreviations are used in the tables:

PG=propylene glycol; DEG=diethylene glycol; NMP=N-methyl pyrollidone;

DMK=dimethylketone; NaST=Na stearate IPA=isopropanol;

MEOH=methanol; 2P=pyrollidone; MIBK=methylisobutyl keton;

CET=cetyl ammoniun bromide; TBT=teriary butanol; TKG=thiodiglycol;

BDL=butane-2,3-diol; PHO=Na₂HPO₄; and P12=propane-1,2-diol.

TABLE I Ex. no. Dye Water PG DEG NMP DMK NaOH Na ST IPA MEOH 2P MIBK 12.0 80 5 6 4 5 2 3.0 90 5 5 0.2 3 10.0 85 3 3 3 5 1 4 2.1 91 8 1 5 3.186 5 0.2 4 5 6 1.1 81 9 0.5 0.5 9 7 2.5 60 4 15 3 3 6 10 5 4 8 5 65 5 2010 9 2.4 75 3 4 5 6 5 1 4.1 80 5 2 10 0.3 2 3.2 65 5 4 6 5 4 6 5 3 5.196 4 4 10.8 90 5 5 5 10.0 80 2 6 2 5 1 4 6 1.8 80 5 15 7 2.6 84 11 5 83.3 80 2 10 2 6 9 12.0 90 7 0.3 3 1 5.4 69 2 20 2 1 3 3

TABLE II Ex. no. Dye Water PG DEG NMP CET TBT TDG BDL PHO 2P P12 2 3.080 15 0.2 5 3 9.0 90 5 1.2 5 4 1.5 85 5 5 0.15 5.0 0.2 5 2.5 90 6 4 0.126 3.1 82 4 8 0.3 6 7 0.9 85 10 5 0.2 8 9.0 90 5 5 0.3 9 4.0 70 10 4 1 411 1 2.2 75 4 10 3 2 6 2 10.0 91 6 3 3 9.0 76 9 7 3.0 0.95 5 4 5.0 78 511 6 5 5.4 86 5 7 7 6 2.1 70 5 5 5 0.1 0.2 0.1 5 0.1 5 7 2.0 90 10 8 2.088 10 9 5.0 78 5 12 5 1 8.0 70 2 8 15 5 2 10.0 80 8 12

What is claimed is:
 1. At least one compound of Formula (1):

which comprises any suitable form of the compound where: p representsfrom 1 to 7 inclusive; the naphthyl moiety may be optionallysubstituted; R¹ is H or at least one of the following substituents,optionally substituted: C₁₋₄-alkyl, NHCOC₁₋₄alkyl, NHCOaryl,NHSO₂C₁₋₄-alkyl, NHSO₂aryl, NHCONR³R⁴ where R³ and R⁴ each independentlyis H, C₁₋₄alkyl or aryl; R² is H, or C₁₋₄ alkyl; L¹ is at least one ofthe following substituents, optionally substituted: —SC₁₋₄alkyleneSO₃H,—NHC₁₋₄alkyleneSO₃H, —NHC₁₋₄alkylene(CO₂H)_(n) where n is 1, 2 or 3,—SC₁₋₄alkylene(CO₂H)_(m) where m is 1, 2 or 3, a moiety of Formula (2)

where: X represents NHC₁₋₄alkylene and Y is NH; L² is one of thefollowing substituents optionally substituted; a moiety of Formula (3)or of the Formula:

or of formula 3:

where: X¹ represents NHC₁₋₄alkylene or a direct link; Y¹ is O or NH; qrepresents from 1 to 7 inclusive; the naphthyl moiety may be optionallysubstituted; and R⁵ and R⁶ each independently is H or at least one ofthe following substituents, optionally substituted: C₁₋₄-alkyl, NHCOC₁₋₄alkyl, C₁₋₄-alkoxy, NHCOaryl, NHSO₂C₁₋₄alkyl, NHSO₂aryl and NHCONR⁷R⁸where R⁷ and R⁸ each independently is H, C₁₋₄alkyl or aryl; where theoptional substituents herein comprise: C₁₋₄alkyl, C₁₋₄haloalkyl,C₁₋₄alkoxy, C₁₋₄haloalkoxy, carboxy, sulpho, hydroxy, amino, mercapto,cyano, nitro and halo; with the proviso that when p is 2 and the two—SO₃H groups in the naphthyl moiety are in the 3 and 7 positions, and ifL² is of Formula (3), q is 2 and the two —SO₃H groups in the naphthylmoiety are in the 3 and 7 positions and with the proviso that if L¹ isan NHC₁₋₄ alkylene SO₃H group, R¹ is an NHSO₂C₁₋₄alkyl, NHSO₂aryl orNHCONR³R⁴ group.
 2. A compound according to claim 1 wherein L² is of theFormula (3) as defined in claim
 1. 3. A compound according to eitherclaim 1 or claim 2 wherein L¹ is —SC₁₋₄alkylene,—NHC₁₋₄alkylene(CO₂H)_(n), —SC₁₋₄alkylene(CO₂H)_(m) or a moiety ofFormula (2).
 4. A compound according to claim 1 wherein: R¹ and R⁶ areboth NHCOCH₃; R³, R⁴, R⁷ and R⁸ are all H; and n and m is eachindependently 1 or
 2. 5. A compound according to claim 1 or 2 wherein pis 2, L² is a moiety of the Formula (3), q is 2, and the two sulphogroups on each naphthyl group are in the 3 and 7 positions.
 6. Acompound according to claim 1 or 2 wherein the compound is in the formof a lithium, sodium, ammonium or substituted ammonium salt.
 7. An inkcomprising at least one compound of Formula (1) as claimed in claim 1,with the exception that Y can be O or NH, and a suitable medium.
 8. Anink according to claim 7 comprising: (a) from 0.01 to 30 parts of thecompound of Formula (1); and (b) from 70 to 99.99 parts of the medium;wherein the parts are by weight and the number of parts of (a)+(b)=100.9. An ink comprising a medium and a compound of Formula (1) as definedin claim
 1. 10. A process for printing a substrate with an ink by inkjet printing wherein the ink is an ink as claimed in claim 7, 8 or 9.11. A substrate printed with an ink as claimed in claims 7, 8 or 9, thesubstrate selected from one or more of: paper, an overhead projectorslide and a textile material.
 12. A process for the colouring a textilematerial with an ink as claimed in claims 7, 8 or 9, the processcomprising the steps of: i) applying the ink to the textile material byink-jet printing; and ii) heating the textile material at a temperaturefrom 50° C. to 250° C. to fix the dye on the material.
 13. A textilematerial coloured with an ink as claimed in claims 7, 8 or
 9. 14. Aprocess for preparing at least one compound of Formula (1) as claimed inclaim 1 the process comprising condensing a compound of Formula (6):

with compounds of formulae L¹H and L²H in which p, R¹, R², L¹ and L² areas defined in claim 1.